Magnetic resonance imaging assessed enteric motility and luminal content analysis in patients with severe bloating and visible distension

Background: Gastrointestinal symptoms in functional gut disorders occur without any discernible structural gut abnormality. Preliminary observations on enteric MRI suggest possible abnormal content and motility of the terminal ileum (TI) in constipation-predominant IBS (IBS-C) with severe bloating, and in functional bloating and distension (FABD) patients. We investigated whether MRI can quantify differences in small bowel (SB) content and motility between patients and healthy controls (HCs). Methods: 11 IBS-C (mean age 40 [21–52] years; 10 women) and 7 FABD (36 [21–56]; all women) patients with bloating and 20 HCs (28 [22–48]; 6 women) underwent enteric MRI, including dynamic motility and anatomical sequences. Three texture analysis (TA) parameters assessed the homogeneity of the luminal content, with ratios calculated between the TI and (1) the SB and (2) the ascending colon. Four TI motility metrics were derived. Ascending colon diameter (ACD) was measured. A comparison between HCs and patients was performed independently for: (1) three TA parameters, (2) four TI motility metrics, and (3) ACD. Key Results: Compared with HCs, patients had TI:colon ratios higher for TA contrast (p < 0.001), decreased TI motility (lower mean motility [p = 0.04], spatial motility variation [p = 0.03], and area of motile TI [p = 0.03]), and increased ACD (p = 0.001). Conclusions and Inferences: IBS-C and FABD patients show reduced TI motility and differences in luminal content compared with HCs. This potentially indicates reflux of colonic contents or delayed clearance of the TI, which alongside increased ACD may contribute to symptoms of constipation and bloating

Geochemical speciation of mercury in bauxite

The presence of trace concentrations of mercury in bauxite is a potential environmental concern in the Bayer alumina refining process. An understanding of the geochemical speciation of mercury in bauxite provides insight into the behaviour of mercury in the Bayer process. The speciation of mercury was evaluated using a novel continuous thermal desorption methodology, sequential extractions, alkaline digestion, aqua regia digestion and hydrofluoric acid total dissolution assay. Thermal desorption demonstrated two distinct mercury forms. Labile mercury was found to be present as metacinnabar or organic-associated mercury, while refractory mercury was associated with quartz or other refractory silicates

MicroRNAs regulate human brain endothelial cell-barrier function in inflammation: implications for multiple sclerosis.

Blood-brain barrier (BBB) dysfunction is a major hallmark of many neurological diseases, including multiple sclerosis (MS). Using a genomics approach, we defined a microRNA signature that is diminished at the BBB of MS patients. In particular, miR-125a-5p is a key regulator of brain endothelial tightness and immune cell efflux. Our findings suggest that repair of a disturbed BBB through microRNAs may represent a novel avenue for effective treatment of MS

Unconventional human T cells accumulate at the site of infection in response to microbial ligands and induce local tissue remodeling

The antimicrobial responsiveness and function of unconventional human T cells are poorly understood, with only limited access to relevant specimens from sites of infection. Peritonitis is a common and serious complication in individuals with end-stage kidney disease receiving peritoneal dialysis. By analyzing local and systemic immune responses in peritoneal dialysis patients presenting with acute bacterial peritonitis and monitoring individuals before and during defined infectious episodes, our data show that Vg9/ Vd2+ gd T cells and mucosal-associated invariant T cells accumulate at the site of infection with organisms producing (E)-4- hydroxy-3-methyl-but-2-enyl pyrophosphate and vitamin B2, respectively. Such unconventional human T cells are major producers of IFN-g and TNF-a in response to these ligands that are shared by many microbial pathogens and affect the cells lining the peritoneal cavity by triggering local inflammation and inducing tissue remodeling with consequences for peritoneal membrane integrity. Our data uncover a crucial role for Vg9/Vd2 T cells and mucosal-associated invariant T cells in bacterial infection and suggest that they represent a useful predictive marker for important clinical outcomes, which may inform future stratification and patient management. These findings are likely to be applicable to other acute infections where local activation of unconventional T cells contributes to the antimicrobial inflammatory response

Association of Accelerometry-Measured Physical Activity and Cardiovascular Events in Mobility-Limited Older Adults: The LIFE (Lifestyle Interventions and Independence for Elders) Study.

BACKGROUND:Data are sparse regarding the value of physical activity (PA) surveillance among older adults-particularly among those with mobility limitations. The objective of this study was to examine longitudinal associations between objectively measured daily PA and the incidence of cardiovascular events among older adults in the LIFE (Lifestyle Interventions and Independence for Elders) study. METHODS AND RESULTS:Cardiovascular events were adjudicated based on medical records review, and cardiovascular risk factors were controlled for in the analysis. Home-based activity data were collected by hip-worn accelerometers at baseline and at 6, 12, and 24&nbsp;months postrandomization to either a physical activity or health education intervention. LIFE study participants (n=1590; age 78.9±5.2 [SD] years; 67.2% women) at baseline had an 11% lower incidence of experiencing a subsequent cardiovascular event per 500&nbsp;steps taken per day based on activity data (hazard ratio, 0.89; 95% confidence interval, 0.84-0.96; P=0.001). At baseline, every 30&nbsp;minutes spent performing activities ≥500&nbsp;counts per minute (hazard ratio, 0.75; confidence interval, 0.65-0.89 [P=0.001]) were also associated with a lower incidence of cardiovascular events. Throughout follow-up (6, 12, and 24&nbsp;months), both the number of steps per day (per 500&nbsp;steps; hazard ratio, 0.90, confidence interval, 0.85-0.96 [P=0.001]) and duration of activity ≥500&nbsp;counts per minute (per 30&nbsp;minutes; hazard ratio, 0.76; confidence interval, 0.63-0.90 [P=0.002]) were significantly associated with lower cardiovascular event rates. CONCLUSIONS:Objective measurements of physical activity via accelerometry were associated with cardiovascular events among older adults with limited mobility (summary score &gt;10 on the Short Physical Performance Battery) both using baseline and longitudinal data. CLINICAL TRIAL REGISTRATION:URL: http://www.clinicaltrials.gov. Unique identifier: NCT01072500

Serum anti-GM2 and anti-GalNAc-GD1a IgG antibodies are biomarkers for acute canine polyradiculoneuritis

Objectives: A previous single-country pilot study indicated serum anti-GM2 and anti-GA1 anti-glycolipid antibodies as potential biomarkers for acute canine polyradiculoneuritis. This study aims to validate these findings in a large geographically heterogenous cohort. Materials and Methods: Sera from 175 dogs clinically diagnosed with acute canine polyradiculoneuritis, 112 dogs with other peripheral nerve, cranial nerve or neuromuscular disorders and 226 neurologically normal dogs were screened for anti-glycolipid antibodies against 11 common glycolipid targets to determine the immunoglobulin G anti-glycolipid antibodies with the highest combined sensitivity and specificity for acute canine polyradiculoneuritis. Results: Anti-GM2 anti-glycolipid antibodies reached the highest combined sensitivity and specificity (sensitivity: 65.1%, 95% confidence interval 57.6 to 72.2%; specificity: 90.2%, 95% confidence interval 83.1 to 95.0%), followed by anti-GalNAc-GD1a anti-glycolipid antibodies (sensitivity: 61.7%, 95% confidence interval 54.1 to 68.9%; specificity: 89.3%, 95% confidence interval 82.0 to 94.3%) and these anti-glycolipid antibodies were frequently present concomitantly. Anti-GA1 anti-glycolipid antibodies were detected in both acute canine polyradiculoneuritis and control animals. Both for anti-GM2 and anti-GalNAc-GD1a anti-glycolipid antibodies, sex was found a significantly associated factor with a female to male odds ratio of 2.55 (P=0.0096) and 3.00 (P=0.0198), respectively. Anti-GalNAc-GD1a anti-glycolipid antibodies were more commonly observed in dogs unable to walk (odds ratio 4.56; P=0.0076). Clinical Significance: Anti-GM2 and anti-GalNAc-GD1a immunoglobulin G anti-glycolipid antibodies represent serum biomarkers for acute canine polyradiculoneuritis

Warming and Resource Availability Shift Food Web Structure and Metabolism

Experimental warming of a marine food web suggests that ocean warming can lead to greater consumer abundance but reduced overall biomass, providing a potentially species-independent response to environmental warming

Electric Field-Tuned Topological Phase Transition in Ultra-Thin Na3Bi - Towards a Topological Transistor

The electric field induced quantum phase transition from topological to conventional insulator has been proposed as the basis of a topological field effect transistor [1-4]. In this scheme an electric field can switch 'on' the ballistic flow of charge and spin along dissipationless edges of the two-dimensional (2D) quantum spin Hall insulator [5-9], and when 'off' is a conventional insulator with no conductive channels. Such as topological transistor is promising for low-energy logic circuits [4], which would necessitate electric field-switched materials with conventional and topological bandgaps much greater than room temperature, significantly greater than proposed to date [6-8]. Topological Dirac semimetals(TDS) are promising systems in which to look for topological field-effect switching, as they lie at the boundary between conventional and topological phases [3,10-16]. Here we use scanning probe microscopy/spectroscopy (STM/STS) and angle-resolved photoelectron spectroscopy (ARPES) to show that mono- and bilayer films of TDS Na3Bi [3,17] are 2D topological insulators with bulk bandgaps >400 meV in the absence of electric field. Upon application of electric field by doping with potassium or by close approach of the STM tip, the bandgap can be completely closed then re-opened with conventional gap greater than 100 meV. The large bandgaps in both the conventional and quantum spin Hall phases, much greater than the thermal energy kT = 25 meV at room temperature, suggest that ultrathin Na3Bi is suitable for room temperature topological transistor operation

Development of a novel splice array platform and its application in the identification of alternative splice variants in lung cancer

Abstract Background Microarrays strategies, which allow for the characterization of thousands of alternative splice forms in a single test, can be applied to identify differential alternative splicing events. In this study, a novel splice array approach was developed, including the design of a high-density oligonucleotide array, a labeling procedure, and an algorithm to identify splice events. Results The array consisted of exon probes and thermodynamically balanced junction probes. Suboptimal probes were tagged and considered in the final analysis. An unbiased labeling protocol was developed using random primers. The algorithm used to distinguish changes in expression from changes in splicing was calibrated using internal non-spliced control sequences. The performance of this splice array was validated with artificial constructs for CDC6, VEGF, and PCBP4 isoforms. The platform was then applied to the analysis of differential splice forms in lung cancer samples compared to matched normal lung tissue. Overexpression of splice isoforms was identified for genes encoding CEACAM1, FHL-1, MLPH, and SUSD2. None of these splicing isoforms had been previously associated with lung cancer. Conclusions This methodology enables the detection of alternative splicing events in complex biological samples, providing a powerful tool to identify novel diagnostic and prognostic biomarkers for cancer and other pathologies